He caused controversy on 2 November when, after scoring his team's second goal away at rivals FC Hansa Rostock (2–0 win), he celebrated with a 'cut-throat' gesture towards the opposing fans.

[4][5] Naki said he was attacked on the street in the Turkish capital by three men shouting racist abuse and challenging him over his support for the Syrian-Kurdish town of Kobane, which is battling a siege by Islamic State (ISIS).

[6][4][1][7] In February 2016, Naki, playing for Amed SK, was suspended for 12 games and received a large fine after allegedly expressing support for the PKK, in the Kurdish-Turkish conflict.

According to writer Patrick Keddie, "In November 2016, a court acquitted Naki of all charges, but the prosecution appealed and in April 2017 he was given an 18-month suspended prison sentence – putting him on probation for five years.

[13] In March 2018, Deniz Naki started a hunger strike in front of the UN building in Geneva, in protest against Operation Olive Branch by Turkish Armed Forces.